Conduction band offset at the $InN∕GaN$ heterojunction

The conduction-band offset between GaN and InN is experimentally determined. $InN∕n$-type GaN isotype heterojunctions grown by molecular beam epitaxy are observed to exhibit Schottky-junction like behavior based on rectifying vertical current flow. From capacitance-voltage measurements on the heterojunction, the Schottky barrier height is found to be $∼0.94eV$⁠. The photocurrent spectroscopy measurement by backside illumination reveals an energy barrier height of $0.95eV$ across the heterojunction, consistent with the capacitance measurement. By combining electrical transport, capacitance-voltage, and photocurrent spectroscopy measurement results, the conduction band offset between InN and GaN is estimated to be $ΔEC=1.68±0.1eV$⁠.